spi: Fix off-by-one error in calculating cycles per data frame

[sifive-blocks.git] / src / main / scala / devices / spi / SPIFIFO.scala

diff --git a/src/main/scala/devices/spi/SPIFIFO.scala b/src/main/scala/devices/spi/SPIFIFO.scala
index a322a1b933004cfe35064d142ad595a037fbef7a..5bc6e823f90ca802e119b53104a5a52de4921aec 100644 (file)
--- a/src/main/scala/devices/spi/SPIFIFO.scala
+++ b/src/main/scala/devices/spi/SPIFIFO.scala
@@ -41,7 +41,7 @@ class SPIFIFO(c: SPIParamsBase) extends Module {
 
   val proto = SPIProtocol.decode(io.link.fmt.proto).zipWithIndex
   val cnt_quot = Mux1H(proto.map { case (s, i) => s -> (io.ctrl.fmt.len >> i) })
-  val cnt_rmdr = Mux1H(proto.map { case (s, i) => s -> (io.ctrl.fmt.len(i, 0).orR) })
+  val cnt_rmdr = Mux1H(proto.map { case (s, i) => s -> (if (i > 0) io.ctrl.fmt.len(i-1, 0).orR else UInt(0)) })
   io.link.fmt <> io.ctrl.fmt
   io.link.cnt := cnt_quot + cnt_rmdr